Elliptical pump and fluid transmission



Jan. 12, 1960 J. T. PEDERSEN 2 ELLIPTICAL PUMP AND FLUID TRANSMISSIONFiled April 4, 1957 '3 Sheets$heet 1 Jens 7i Pedal-sen ZNVENTOR.

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ELLIPTICAL PUMP AND FLUID TRANSMISSION Filed April 4, 1957 sSheets-Sheet 2 Fig.2

Jens 7T Pedersen F/g 7 38 INVENTOR.

IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII N kidm D eeeeeeeeeeee t3 ELLIPTICALPUMP AND FLUID TRANSMISSION Jens T. Pedersen, Plymouth, Mich, assignorof one-half to Edith Pedersen, Plymouth, Mich.

Application April 4, 1957, Serial No. 650,623

6 Claims. Cl; 103-134 This invention comprises a novel and usefulelliptical pump and fluid transmission and more particularly relates toan expansible chamber, device adapted for use as a fluid pressure pumpor motor. I

The principal purpose of this invention is to provide a fluid pressurepump or motor of the expansible chamber type and wherein all of themoving parts thereof shall have a substantially continuous rotation.

A further object of the invention is to provide a pump or motor in whichthe working chamber in the stator shall be of an ellipticalconfiguration and wherein the piston elements of the rotor shall be soshaped and proportioned as to have a continuous sealing engagement withthe walls of the working chamber throughout their rotation through theworking chamber.

A further and more specific object of the invention is to provide afluid pump or motor having an elliptical ring-like working chambertogether with a rotor having a plurality of elliptical shaped pistonseach revolving continuously throughout the elliptical working chamberand having such geometry as to structure and motion as to maintain atight sealing engagement with the walls of the working chamber at alltimes during the rotation of the piston elements.

A still further important object of the invention is to provide a fluidpump or motor which shall have a rela: tively small number of parts andwherein the same shall be very compactly assembled to effect adependable and long lived operation.

These together with other objects and advantages which will becomesubsequently apparent reside in the details of construction andoperation as more fully hereinafter described and claimed, referencebeing had. to the accompanying drawings forming a part hereof, whereinlike numerals refer to like parts throughout, and in which:

Figure 1 is a perspective view showing a suitable embodiment of a fluidpump or motor in accordance with this invention, a part of the powershaft being broken a y;

Figure 2 is a vertical central sectional view through the apparatus ofFigure 1, being taken substantially upon the plane indicated by thesection line 22 of Figure 1;

Figure 3 is a horizontal sectional view taken substantially upon theplane indicated by the broken section line 33 of Figure 2; I

Figure 4 and Figure 5 are vertical transverse sectional views takensubstantially upon the planes indicated by the section lines 44 and 5-5,respectively of Figure 2 and showing in particular the geometry of theworking chamber and of the piston elements therein;

Figure 6 is a detail view taken substantially upon the vertical planeindicated by the section line 66 of Figure 4 and showing the manner inwhich the piston elements are pivotally connected to the carrier platesof the rotor for oscillation about spaced parallel axes; and

Figure 7 is an exploded perspective view showing the 1W0 carrier platesand the piston elements of the rotor Patented Jan. 12, 1960 ice and astationary core which forms the inner peripheral wall of the ellipticalworking chamber of the device.

In the accompanying drawings is exemplified an embodiment of anapparatus in corporating therein the principles of this invention. Ingeneral, the invention comprises a novel fluid motor or pump consistingof a stator having an elliptical workingv chamber in which is rotatablydisposed a rotor having a plurality of elliptical bodies forming pistonsand which are maintained in a constant parallel relation to each otherduring their rotation throughout the elliptical working chamber.

-It should be understood that the, invention is not limited in utilityto any single specific purpose, but is broadly useful wherevera'po'sitive displacement type of pump or motor is desired, as forexample in hydraulic drive mechanisms wherein a pump operates one or aplurality of motors as for example in use in automobiles, locomotivesand the like. Further, the positive displacement of the fluid medium andthe pistons of the rotor provide a highly eflicient and precisemechanism for controlling the conversion of power between a flowingfluid medium and a rotatable power shaft.

It will be further understood that-the apparatus illustrated in theaccompanying drawings and described hereinafter in the specification maybe constructed in various sizes as desired. The geometry of constructionand of motion of the piston elements of the rotor and the ellipticalworking chamber of the stator is such that each elliptical pistonelement is moved throughout the chamber while being maintained in aparallel position to itself and to the other elements whereby the pistonelements have a continuous sealing engagement with the inner and outerperipheral walls of the elliptical working chamber.

In the accompanying drawings, the apparatus consists of a stator 10comprising a drum-like element open at its two sides and having a pairof end plates comprising end walls 12 and 14 for closing the same,suitable fastening bolts 16 being provided for detachably securing theend walls to the drum-like member.

The two end walls 12 and 14 have outwardly projecting hubs 17 and 18respectively, the hubs being displaced vertically from each other aswill be apparent from Figure 2, the hub 17 comprising a diametricallyenlarged hub 20 where it joins the end plate, and a diametrically reduced hub 22. -S imilarly,.the hub 18' of the end plate 14 has thediametrically enlarged hub 24 at its junction with the end plate 14,together with a diametricallyreduced outwardly projecting hub 26. From acomparison of Figures 2 and 3 it will be seen that the hubs 17 and 18are disposed in the same vertical plane or are in vertical alignmentwith each other but are vertically spaced for a purpose to besubsequently set forth.

As will be best apparent from Figures 2 and 3 in conjunction with Figure1, it will be seen that the end plates 12 and 14 are provided with aplurality of radially extending reinforcing webs or fins 28 and 30respectively which extend from the peripheryof the end plates intojunction with the hubs 20, 22 and 24, 26.

Referring now particularly to .Figures 2 and 3 it will be seen that thedrum-like member 10 has its opposite side faces provided with circularrecesses 32 and 34 respectively. Between the faces the member 10 isprovided with an internal peripheral wall 36,,which as shown in Figures4 and 5 is of a generally elliptical shape. This wall comprises theouter peripheral wall of an elliptical working chamber of thepump ormotor as will become subsequently apparent.

Received within the central chamber of the hollow stator member 10 is acentrally disposed core or body 38 carried by a mounting or supportingshaft 40. The core has an outer periphery 42 which is of an ellipticalshape corresponding to that of the wall 36, and the surface 42 comprisesthe inner wall of the elliptical working chamber of the device. It willbe noted from Figures 4 and 5 that the inner and outer walls 42 and 36respectively are equidistantly spaced to thus provide an ellipticalworking chamber having a uniform depth.

The mounting shaft 40 extends into the hub 26 of the endplate 14 and isfixedly secured thereto as by a pin 44, whereby the core is stationarilysecured rigid with the stator. v

Received within the stator, in the central chamber thereof between thedrum-like member and the end plates 12 and 14 is a rotor assembly, theelements of which are shown in Figure 7. This rotor includes a pair ofcarrier plates 50 and 52 which are preferably circular and of the samesize. The plate 50 is received in the previously mentioned circularrecess 32, of the drum like member 10, while the plate 52 is received inthe corresponding recess 34. The axes of the recesses are verticallyspaced from each other in the same manner as the spacing of the hubs 17and 18 previously men.- tioned, in order that the two carrier plates mayrotate about axes which are vertically spaced from each other, Thecarrier plate 50 has an outwardly extending hub 54 which is rotatablyreceived and journaled in the hub 20 of the end plate 12, and fixedlysecured in this hub 54 as by a pin 56 is a power shaft 58 which in turnis journaled in the hub 22. Suitable journal and thrust bearings 60 areinterposed between the power shaft, the hub 54- and the interior of thehubs 22 and 20.

Power shaft 58 constitutes a means whereby rotation may be imparted tothe rotor when the device is intended to function as a pump, or wherebypower may be taken from the rotor when the device functions as a fiuidmotor or turbine.

The other carrier plate 52 is likewise provided with an outwardlyprojecting hub 62 which is journaled in the hub 24 of the end plate 14and upon the mounting shaft for free rotation thereon as by a suitableradial, pressed bearing member 63.

As so far described, it should be noted that the carrier plate may beconsidered as constituting a power or driving plate, while the carrierplate 52 constitutes an idler or driven plate.

The combination of the two carrier plates 50, 52 and the peripheralinner and outer surfaces 42 and 36 constitute the elliptical workingchamber of the pump or motor, in which are disposed for continuousrotation a plurality of pistons carried by the carrier plates in amanner to be now described.

The carrier plate 50 is provided with a set of pins 64,

while the other carrier plate 52 is provided with a second set of pins66. These pins project toward each other and are of a length notexceeding the .distance between the two carrier plates when mounted asshown in Figures 2, 3 and 6. The two sets of pins thus form pairs ofpins, each pair comprised of one pin on each plate, and the pins of eachpair are disposed in vertically spaced relation as will be best apparentfrom Figures 4, 5 and 6. The pins 64 are arranged in a circle about theaxis of rotation of the carrier plate 50, while the pins 52 are disposedin a circle of the same radius about the axis of rotation of the carrierplate 52. Thus each pin 66 of the carrier plate 52 is vertically offsetbelow its corresponding pin 64 of the other carrier plate 50.

The piston elements comprise a plurality of elliptical bodies 68, eachhaving a pair of bores 70 and 72 therein. The bores 70 of each pistonreceives one of the pins 66 of the carrier plate 52, the bores 72receive the pin 64 of the carrier plate 50. By this means, each of theelliptical piston elements is maintained-in a constant attitude so thatas .the two carrier plates of the rotor revolve, the piston elementswill ,travel continuously throughout the elliptical working chamber,formed between the inner and outer ,walls .42 -an d .36, respectively,with the piston elements being maintained parallel to 4 each otherthroughout their rotation through the working chamber.

The dimensions of the piston elements are such that they will at alltimes maintain a continuous sealing engagement with the inner and outerwalls of the working chamber, as will be apparent from Figures 4 and 5.It will be understood that the geometry of the pistons and. theelliptical'inner and Outer walls of the working chamLI- her are such asto efiect this operation.

Referring now particularly to Figures 4 and 5 it will be seen that meansare provided for introducing a fluid intothe working chamber and forexhausting a fluid therefrom. Conveniently, two such inlet and outletmeans. are provided upon opposite sides of the axis of rotation of therotor. Thus, aligned fluid inlet and outlet passages and 82 are providedin the upper portion of the stator, and corresponding inlet and outletpassages 84 and 86 are provided in the lower portion thereof, the twosets of aligned passages being parallel to each other. Internallythreaded bosses 88 are provided at the outer ends of each of thesepassages whereby suitable fluid conducting conduits or connections maybe made with the device. At their inner ends, the inlet and outletpassages merge smoothly into the outer elliptical peripheral wall of theworking chamber.

By virtue of the tight sealing engagement between the piston elementsand the inner and outer walls of the working chamber, -,'it will be seenthat there is a positive displacement of fluidfrom an inlet passage toan outlet passage. Thus, if the device is employed as a pump, there willbe a positive impelling of fluid from the inlet passage, through theworking chamber into the outlet passage for each of the upper and lowersets of fluid inlet and outlet means. Conversely, if the device isemployed as a motor, the passage of fluid under pressure from the inletpassage to the outlet passage through the working chamber will produce apositive displacement of the pistons and thus a precise rotation of therotor and of the power shaft connected therewith.

The foregoing is considered as illustrative only of the principles ofthe invention. Further, since numerous modifications and changes willreadily occur to those skilled in the art, it is not desired to limitthe invention to the exact construction and operation shown anddescribed, and accordingly all suitable modifications and equivalentsmay be resorted to, falling within the scope of the invention asclaimed.

What is claimedas new is as follows:

1. A pump .or motor-comprising a stator having an annular workingchamber therein of elliptical shape, a plurality of pistons in saidchamber and means supports v ing said pistons in fixed parallel relationfor rotation through said chamber, said stator including, a drum-likemember having a concave surface, constituting the radially outer wall ofsaid chamber and a pair of end walls having parallel hubs, a pair ofshafts each mounted in one of said hubs and extending into said chamber,one of said shafts being fixed to its hub and an eccentric bodyfixed onsaid'one shaft and disposed in said drumlike member to comprise theradially inner circumferen- =tial Wall of said chamber, said supportingmeans including a pair of carrier plates constituting side walls of saidchamber and each mounted on one of said shafts for rotation and disposedwithin said drum-like member, means pivotally securing each piston toboth of said carrier plates for oscillation of said pistons about theparallel axes of their connections with the two carrier plates inresponse to rotation of the latter about the parallel ,axes of saidshafts, means for introducing fluid into said chamber and means forexhausting fluid from said chamber.

2. The combination of claim 1 wherein the opposite sides of saiddrum-like member have eccentrically disposed circular recesses receivingsaid carrier plates, said end plates retaining said carrier plates insaid recesses.

3. The combination of claim 1 wherein one carrier plate is rotatableupon said one shaft and the other carrier plate is fixedly secured tothe other of said shafts.

4. The combination of claim 1 wherein said carrier plates have hubsjournaled in the hubs of said end walls.

5. The combination of claim 1 wherein the opposite sides of saiddrum-like member having eccentrically disposed circular recessesreceiving said carrier plates, said end plates retaining said carrierplates in said recesses, fastening bolts extending through saiddrum-like member and each of said end plates and detachably securingthem together.

6. The combination of claim 1 wherein the opposite sides of saiddrum-like member have eccentrically diaposed circular recesses receivingsaid carrier plates, said end plates retaining said carrier plates insaid recesses, said eccentric body being engaged on opposite sides bysaid carrier plates and spacing the latter.

References Cited in the file of this patent UNITED STATES PATENTS1,467,944 Mason Sept. 11, 1923 1,580,808 Borden Apr. 13, 1926 1,700,038Feuerheerd J an. 22, 1929 FOREIGN PATENTS 167,360 Austria Dec. 27, 1950

